Born in Vienna to a Jewish family, Alfred was the younger brother of Julius and Bertha Braunthal, who both later became prominent in the workers' movement.
Alfred studied philosophy, history and economics in Vienna and Berlin, receiving a doctorate in 1920.
[1] When the Nazis came to power in Germany, Braunthal fled to Belgium, where he spent time as Hendrik de Man's assistant.
There, he began as research director of the United Hatters, Cap and Millinery Workers International Union, his writing on economics becoming more concerned with immediate, practical matters, and becoming influenced by John Maynard Keynes.
[1] In 1949, Braunthal became the first head of the economic and social department of the International Confederation of Free Trade Unions, based in Brussels.